Chaining finger and seam gauge for overseam sewing machines



Nov. 21, 1933. A, KLEMM 1,935,640

CHAINING FINGER AND SEAM GAUGE FOR OVERSEAM SEWING MACHINES Filed Feb. 15, 1952 INVENTOR HAJIZemm ATTORN Y Patented Nov. 21 1933 UNITEDSTATES CHAINING FINGER AND SEAM GAUGE FOR OVERSEAM SEWING MACHINES Hermann A; Klexnm, Mamaroneck, N. Y. Applieation February 15, 1932. Serial No. 592,902

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contiguous peripheral portions of the flanges of the feeding wheels and a looper to co-operate with the needle to intersect the thread and form the stitch, means alsobeing provided relative to the feeding wheels to gauge the W1 th of the seam and embodying a chaining finger or tongue to intersect the path of movement and co-operate with the needle and looper to regulate the size of the loops of the stitches and effect a chaining of the thread loops after thematerial being stitched passes from between the feeding wheels and whereby to effect ready stitching of successive material. v a

In order to produce a very narrow seam and a loop of small size to form a tight stitch the chaining finger must be of very small cross sectional area or thickness and is therefore made to conform in size and shape substantially to that of the pointed end portion of a sewing needle. As the finger is constructed integral with the seam sizing gauge it is costly to produce since it is not only necessary to replace the chaining finger when it is broken but also the gauge. Dueto the size of the chaining finger it is necessarily frail with the result that it is easily broken, which happens frequency due to the jamming of material between the feeding wheels and other causes.

It is the object of the present invention to provide an improved constructed and arranged seam gauge and chaining finger to overcome the above isadvantages by constructing the chaining finger and seam gauge separately and arranging the same for removably mounting of the chaining finger upon the seam gauge.

In the drawing accompanying and forming a part of this application only so much of an overseaming sewing machine is shown as is essential to an understanding of the invention, Figure 1 being a plan view of an embodiment of my invention mounted on a supporttherefor and showing the same in relation to a pair of fabric feeding wheels of an overseam sewing machine.

Figure 2 is a side elevation of, one of the fabric feeding wheels and showing my improved gauge and chaining finger mounted on its support in relation thereto.

Figure 3 is a plan view of the seam gauge-and 'reciprocatory needle 1'7.

chaining finger showing the same dissembled; and I V Figure 4 is a view of the seam gaugelooking at the bottom of Figure 3 and showing the chaining finger mounted thereon.

The invention is shown in connection with the fabric feeding means for feeding fabric or other material to be stitched relative to stitching mechanism, embodying a needle and co-operating looper, of an overseam sewing machine of the Union specia type comprising a pair of intermittently rotated cupped or peripherally flanged wheels 5, 6 fixed to shafts 7 to rotate in a horizontal plane with the flanges extending upward and the outer surface transversely serrated and arranged with a peripheral portion of the wheel fianges incontiguous relation to each other, the fabric F, shown in dot and dash lines, being engaged between the serrated surfaces of the wheels and adapted to be fed by the rotation of the wheels.

i To determine the width of the seam there is provided a gauge to overhang the contiguous portions of the wheel flanges and spaced a predetermined distance above the edge "of the wheel flanges, said gauge being in theform of a lip 30 8 arranged at one end of an arm 9 and whereby it is mounted by screws 10 upon a supporting bracket 11, mounted to have adjustment relative to the flange of the wheel 5 by a screw engaged in an elongated opening 12 in the bracket and 95 threaded into a fixed part of the machine. The bracket 11' has a forward extending arcuate portion 13 the curvature of which conforms to the curvature of and engages with the inner surface of the flange of wheel 5 and extend beyond the end of the lip 8, said extended portion having a ledge 14 to engage over the top of the wheel flange with the outer surface of said ledge extending in the arc of and flush with the outer surface of the wheel flange with the portion extending beyond the lip 8 of less thickness than the remainder of said led e, as shown at 15 in Figure 2. This ledge has a transverse recess 16 at the juncture of the portion 15 of reduced thickness and at the end of the lip 8 for the passage of the 1 0 The under surface of the lip is provided with a guiding and gauge surface 18 for the fabric fed between the wheel flanges in the form of a recess of arcuate shape in cross section and tapering or converging from 5 the rear end to the forward end of the lip and extending in the plane of travel of the fabric from between the feeding flanges of the wheels 5, 6, the spacing of said surface of the recess above the edges of the wheel flanges and the engagement of the edges of the fabric therewith determining the positioning of the marginal portions of the fabric relative to the recess 16 and passage of the needle 17 and thereby the width of the seam.

In order to effect a chaining of the loops formed by the piercing of the fabric by the thread carrying needle 17 and the looper (not shown) cooperating therewith, particularly after a. piece of fabric has been stitched and passed from between the feeding wheels to maintain the loop and thus readily effect the stitching of a successive piece of fabric without the necessity of possibly rethreading the needle and the forming of a preliminary loop, there is extended forward of the lip 8 a finger, termed a chaining finger, said finger being extended forward from the lip 8 and beyond the recess 16, the chaining finger converges to a point and for the major portion of the length thereof extends substantially tangential to the edges of the flanges or rims of the wheels 5, 6 above and in the line of feed of the fabric from between the flanges of the feeding wheels 5, 6. The cross sectional area or thickness of this finger must be proportional to the positioning of the gauge surface 18 above the wheel flanges and width of seam to produce a loop of a size necessary to effect a tight stitch. This finger heretofore has been constructed integral with the gauge lip 8. In the production of very nar row seams, as, for instance, in stitching silk hosiery, in order to produce a tight stitch this finger must be of a thickness approximately that of an ordinary sewing needle with the result that itis not only difficult to construct it integral with the gauge lip 8 but as it is frail it will be broken by a slight strain with a consequent necessity of frequently replacing it, which also necessitates the replacing of the gauge lip carrying arm. To overcome this disadvantage the finger 19 is constructed separate from the gauge lip carrying arm and removably mounted thereon, the chaining finger constituting substantially the pointed end portion of a sewing needle. To removably mount the chaining finger upon the gauge lip 8 a slot 20 is extended into the forward edge of the lip centrally between the sides with the opposite side walls of the slot preferably slightly converging toward each other from the top surface to the bottom surface of the lip, the finger being engaged into said slot with the end abutting the end wall of the slot and secured therein by suitable means, as by soldering.

Having thus described my invention, I claim:

1. A seam gauge and chaining finger for chain stitch sewing machines, comprising an arm adapted at one end for mounting on a support and a lip extended from the opposite end having a recess in one face of arcuate form in cross section and converging from the rear end to the forward'end of the lip to serve as a material guide and gauge and having a slot extended inward from the forward edge, and a chaining finger removably mounted at one end in the lip slot to extend forward of the lip.

2. In a chain stitch sewing machine, the combination with a pair of peripherally flanged rotatable feeding wheels having peripheral portions juxtaposed and between which the material to be stitched is fed, of a member mounted to extend over the juxtaposed peripheral portions of the wheel flanges and in the line of feed of the material from between the feed wheels, said member having a recess in the underface for engagement of the edges of the material to be stitched to guide the material and gauge the width of the seam, and a chaining finger removably mounted in the front end of said member and extending forwardly thereof above and in the line of feed of the material from between the feed wheels.

3. A seam gauge and chaining finger for chain stitch sewing machines, comprising an arm adapted for removably mounting on a support and having a lip extended therefrom arranged as a guide and gauge for, the edges of the material to be stitched, and a chaining finger removably mounted in the end-of and extending beyond the lip.

HERMANN A. KLEMM. 

